The Commotion over the New Cornea Layer

Hundreds of researchers emailed its discoverer to congratulate him for it.

Well over 200,000 people viewed one announcement of it. There were 1,800 comments and 12,000 “Likes” on a Huffington Post story about it. There were 13,000 reddit.com “upvotes” and 9,991 “downvotes” for it. It was so cyber-famous it had its own Wiki page the dayafter its press release broke.

Then there was the Real World. Five of six speakers at a recent conference opened their presentations with, “I have to change my talk because of it.” And by year’s end, the man behind it will have given 21 major talks on it.

The “it” is the recent discovery of a tiny, 1/25,000th of an inch, new layer that appears in the eye after certain surgeries that may or may not change textbooks; may or may not improve critical eye surgeries. Time will tell.

Don’t tell that to the cyberworld.

“It’s all been a huge distraction,” says a cheerful Harminder Dua, discoverer of the so-called new “Dua’s Layer.” “But I’ve certainly enjoyed some of it.”

As the University of Nottingham chair of ophthalmology, co-editor-in-chief of the British Journal of Ophthalmology, and past/current president of many professional societies, Dua noticed some surgeries reveal what some called corneal “residue,” others a “split” sometimes forming in the cornea’s Descemet’s membrane. He thought it was a different tissue.

He investigated. Using a technique from deep anterior lamellar keratoplasty (DALK), he sent air puffs into eyebank corneas (average age: 77), forming a bubble in each. Off each, he peeled Descemet’s membrane. Then he was able to form another bubble—indicating another layer that was tough, withstanding a pressure of 700 to 750 mm of Hg.

His paper was accepted by the world’s #1 eye journal: Opthamology. He presented data, embargoed, to a wowed conference. On May 28 the journal postedit.

But it was on June 11, after the Nottingham press release came out, that it went viral. The release phrase “textbooks will literally need to be rewritten” was highlighted in huge letters by reddit in its link.

The lay public commotion thus seemed linked to the release’s “rewritten textbooks” phrase, which wasn’t in the paper. “I didn’t say it,” Dua laughs. He had simply noted the head of a top opthamology society said it after a presentation. “But it was too late” by the time he saw the release stating he said it. “It was out.”

There is not yet global academic support for a textbook change. Such changes occur book by book.

Peter McDonnell, Johns Hopkins Wilmer Eye Institute director, told The Ophthalmology Times (OT) time is needed “to see if others can confirm the existence of this ‘new layer’ and its potential significance. My view is that this is an interesting and provocative report from a well-respected research group. My reading of their paper is that this is not a description of a new layer in the sense of how we think of the corneal layers (epithelium, basement membrane, Bowman’s layer, etc.), in which the composition is distinct and readily appreciated as such on light and electron microscopy (or even at the slit lamp)…It will be interesting to see how other means of testing for this confirm or refute the finding and to what degree this might prove to have clinical significance.”

Oregon Health Sciences University clinical ophthalmology professor Mark Terry told The OT: “Dr. Dua has taken a new approach to looking at the posterior layers of the cornea and proposes that because the posterior layers of the stroma just anterior to Descemet's membrane react differently to our surgical maneuvers than, say, the mid-stroma, this property qualifies this layer as a separate anatomical entity….I applaud the fresh approach to corneal anatomy that Dr. Dua has taken, and I look forward to further documentation of the unique benefits of this layer in treatment.”

The OT, of which McDonnell is chief medical editor, said the find is “expected to have an effect on posterior corneal surgery and the understanding of corneal biomechanics and posterior corneal pathology.”

Dua is working on many follow up papers. A surgeon says he found the layer in a 9 year old. Four specialists say it is affected by macular corneal dystrophy. Specialists worldwide “are sending images.”

The most immediate effect, he says, will be on Descemet’s Membrane Endothelial Keratoplasty (DMEK), a key corneal transplant technique.

“Whether people agree there is a new layer—and I think most do—they can see it will make DMEK more doable. Now only a few centers do it. It is so challenging. The new layer will make it easier, as it is so strong it supports Descemet’s.”

Generally, when a cornea’s inner lining is diseased, much tissue is replaced, which can cause rejection. DMEK lets surgeons just replace the inner lining. Still, it is so thin it can tear. Removing Dua’s layer, too, strengthens tissue.

“Most split the cornea, dissect the innermost 150 microns, transplant. Why not just peel the Descemet’s membrane and Dua’s? Instead of 150 microns, you remove 30.”

Textbooks aside, Dua has entertained his daughter , who loves the posts. Their favorite: a man said, “Great discovery. but what is he wearing on his head, give me a break.” (As a sikh, he wears a turban.) An argument about sikhs ensued. “A lady said: “What did Jesus say to Harminder Dua? ‘Sikh’ and thou shall find.”